Reversing apparatus for heating furnaces



March 18 1924.

G. 1H, ISLEY REVERSING APPARATUS FOR HEATING FURNACES l Filed Dec, 2s,1913 :s sheets-sheet l.

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G. H. ISLEY REVERSINGVAPPARATUS F013 HEATING FURNAGES Filed Dec.

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March 18 1924. 1,487,332

G. H. lsLEY REVERSING APPARATUS FOR HEATING -FURNACES Filed nec. 26,v1918 5 Sheets-sheet 5 Patented Mar. 18, 1924.

UNITED STATES PATENT OFFICE.

GEORGE H. ISLEY, OF WORCESTER, MASSACHUSETTS, ASSIGNOR T0 MORGAN CON-STRUCTION COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION 0FMASSACHUSETTS.

REVERSING APPARATUS FOR HEATING FURNACES.

Application filed December 26, 19'18. Serial No. 268,391.

T0 all whom t may concern:

Be it known that I, GEORGE H. IsLnY, a citizen of the United States,residing at Worcester, in the county of Worcester and Commonwealth ofMassachusetts, have invented a new and useful Im rovement in a ReversingApparatus for eating Furnaces, of which the following, together with theaccompanying drawings, is a specification.

The present invention relates to improvements in the apparatus which isused with the regenerative type offurnace for reversing the coursethrough such a furnace of the burning gaseous fuel.

The present invention partakes, in part, of the principles of operationwhich characterize the reversing apparatus forming the subject matter ofmy United States Letters Patent No. 1,408,946, dated March 7, 1922. Thepresent invention contemplates various novel and improved features inapparatus of this class, involving changes in the construction,arrangement, and mode of operation of the apparatus of my aforesaidLetters Patent, all of which improvements and changes are set forth indetail in the following description. In connection with saiddescription, reference is had to the accompanying drawings, wherein Fig.1 is a plan view of one of the reversing units which constitutes myinvention.

Fig. Q is a side view of the apparatus shown in Fig. 1, certain partsybeing broken awayv to disclose more clearly the construction thereof.

Fig. 3 is a longitudinal sectional view on the line 3 3 of Fig. 1.

Fig. 4 is a transverse sectional view on the line 4-4 of Fig. 3.

Figs. 5 and 6 are diagrammatic views illustrating various applicationsof my invention to a regenerativeffurnace of well known type.

Fig. 7 is a detail view illustrating the construction of the mechanismfor controlling the operation of the reversing apparatus.

Like reference characters refer to like parts in the different figures.

In my aforesaid Letters Patent there is disclosed the utilization invarious forms of a selectively movable hood structure adapted toestablish communication between different pairs of a series of alinedflue terminals, and to be moved out of operative relation tol other flueterminals. Associated with certain of said flue terminals are swinginggravity-closed covers, each of which is adapted to be automaticallyopened by the movement of said hood structure into operative positionwith respect to its associated flue terminal. In said Letters Patent,various adaptations of the foregoingv principle to the reversal ofcombustion products in a furnace are illustrated; these range from theprovision of three independent single hood structures, associated withthree sets of coterminous furnace fiues, to the provision yof afour-part hood structure associated with a series of ten coterminousfurnace lues.

The present invention is based upon the same principle, involving hoodstructures having a translatory motion, that is present in the inventionof my aforesaid Letters Patent. As distinguished from the invention ofsaid Letters Patent, the present invention contemplates a novelarrangement and disposition of parts whereby two compound hoodstructures, identical in all respects, are enabled to eect the operationof reversing a furnace, in such a manner as to permit the disposition ofthe reversing instrumentalities in close proximity to the regeneratorsof the furnace, thus simplifying and minimizing the construction of theflues. Other important objects and advantages of the present invention,including an operating mechanism for said hood structures, will be madeclear as the description thereof proceeds.

As shown in the diagram of Fig. 5, which illustrates the application ofmy invention to a heating furnace,the heating furnace 1, of any wellknown type, is provided at it-s opposite ends with the usual gasregenerator passages 2, 2 and the usual adjacent air regeneratorpassages 3, 3', arranged in the manner common to devicesof this class.In the use of the duplicate reversing instrumentalities of my inventionfor such a furnace, five coterminous flues are arranged at each end otthe furnace, adjacent the respective regenerators, and a hoodstructure 1. et" is operativel;y disposed in connection with each set ofVline terminals. In each set ot said terminals.l as illustrated in Figs.5 and 6, the gas regenerator passages 2, 2 connect with gas regeneratorlines 5, 5, and the air regenerator passages 3, 3 connect with airregenerator lines 6, 6. Between the air and gas regenerator fines 5, Gand 5. G are disposed a pair of stack lines 7. T and 7. T. which areconnected to a common stack passage 8. In alinement. with the tlue'terminals above described are gas supply line terminals 9, 9; in Fig. 5these and the adjacent gas regenerator terminals are disposed on theoutside of the sets, while in Fig. 6. the arrangement is such that thegas lines are disposed on the inside ot eachset; it is obviouslyimmaterial which arrangement is adopted.

Each of the duplicate reversing instrumentalities is of the constructionshown in F .k 1, and 4, consisting essentiallv o'lr a pair ot hoods,`movable in unison, and each adapted to bridge over two adjacent tlueterminals olf its associated set, leaving alwa vs unbridged either theair '['lue 6, 6 or the gas tine 9, as the. case may be. It will be wellunderstood that under `these conditions. with the reversinginstrumentalities l. l in the positions shown in Figs. 5 and the passageof air and gas through the furnace 1 is from right to lett; when saidinstrumentalities are moved to their other positions, so as to cover thegas flue 9, and uncover the gas flue 9, the direction of the products ofcombustion through the furnace is reversed. The present invention isconcerned with the provision of improved apparatus tor this purpose,together with a novel and etlicient operating mechanism tor suchapparatus.

As shown in Fig. 3, a water seal casting l() is utilized to provide theseveral alincd tine terminals G, '7, T, and 9, which register with thecorresponding passages provided in the lnickwork 11, the two terminals7, i opening' from a single passage S. This water seal casting 10provides a surrounding rim or flange 12, which is adapted to maintain asul'licient depth of water around and between all of said flueterminals, as will be well understood. On opposite sides, near each end,the castingl 10 has bearing lugs or projections ill, which providetrunnions for the pivotal support oit bell crank levers 14, 14e, onenear each ot the four corners ot the casting. @t these tour identicalbell crank levers 1st, 1l, the two at one end of the casting areoppositelv disposed from those at the other end of the casting. In otherwords, in the position ot the parts shown in Fig. 2, the levers 11i atthe lett hand end have their shorter arms directed downwardly, while thelevers at the right hand end have their shorter arms directed upwardly.

The long arms ot these bell cranks 1l, 14 are utilized tor the movement:of a hood supporting structure 15, in the shape of a generallvrectangular framework, having a central transverse partition 1G. Thesides and ends ot the structure 15 and also its partition 1li areprovided with a depending flange 1T, that is adapted to dip beneath theWater in the casting 10 for the purpose of providing a seal, ashereinafter described. The structure 15 is adapted to support a pair ofhoods 18, 18, which meet at the central transverse partition 1G of saidstructure. The snpptnling surface ot the structure 15, on which theedges of these hoods rest, is snitablv flanged, as at 19, 19',interiorly and exteriorlv, to make provision lor a sand seal or the likearound the edges of said hoods, which prevents the escape of gastherefrom and at the same time makes said hoods rcadiljv andsej'nxrateljremovable, for the inspection and repair of the same or theparts that are covered thereby.

The structure 15 provides at each corner a lng 2') for the pivotalconnection thereto ol" the long arms o'l" bell cranks 1l, la. These longarms of said bell cranks are parallel, and thus provision made forimparting to the structure 15 and hoods 18 a parallel motion withrespect to the two axes of rotation of said bell cranks. The short armsof the bell cranks at opposite ends, which though parallel extend inopposite directions, have pivotallv connected thereto tubular links 21,21 that extend toward each other. A rod 22 is telescopicallv carried bysaid links with its ends projecting into the bore ot' each one, so as tomaintain them in alinement. Fach link Q1 terminates in a tlange orcollar 23, as shown in connection with one of these links in Fig. 2.Said collars Q3 are adapted to slide in a tubular casing 2l whichsurrounds the adjacent ends ot' the two links Q1, 21. Between eachcollar 23 and the adjacent end of said casing is i confined a spring 25,which surrounds that portion ot its link 2l that extends into thecasing.

In the position ot the parts illustrated in Fig. 2, with the structure15 and the two hoods in their extreme right hand positions. the severalsprings two on each side of the apparatus, are under extremecompression, and are therefore tending, through thc collars Q23 andlinks 21. to rock the bell cranks 14 in a counter-clockwise direction.wing to the forces thus exerted by these springs, the act of moving thestructure 15 and hoods 18 toward the left, about the centers ot' bellcranks 14, requires only a relatively small torce, in comparison to thatwhich would otherwise be required to effect this combined translatoryand lifting move- 1n`ent. Inl other words, by the arallel motionthusprovidedy for, the ten ency of the springs 25 is, at the inceptionof the movement, to draw the short arms of the bell cranks 14 together,thus minimizing the force required initially to raise the structure thatis carried by the long arms of said bell cranks. The springs 25, as willbe evident, reach the limit of their expansion toward each other whenthe long arms of the bell cranks 14 have reached a vertical position;under these conditions, the short arms of' said bell cranks, the links21 and the tubular casing 24 all lie in the same horizontal plane, withthe minimum distance between thev ends of said short arms. From thispoint on, the motion of translation of the hood structure is combinedwith a descending motion, by which the force of gravity is renderedavailable to compress the springs 25. At the end of this movement, aswill readily be seen, the telescoping structure that connects the shortarms of the bell cranks is again at the limit of its distention, but itsposition is the reverse of that shown in Fig. 2, that is, saidtelescoping structure is inclined in the oppositesdirection. In thisway, a force is stored up to assist in the movement of the-hoodstructure back to the position illustrated in Fig. 2, which forcebecomes available for the initial lifting of said structure to therebyminimize the power required for its operation.

The power required for rocking the bell cranks 14 in the manner abovedescribed is obtained fromy a motor or other prime mover 26, on theshaft of which is mounted a pinion 27 in mesh with a gear 28 on a shaft29. The latter carries a worm 30 which drives a worm wheel 31 on atransverse shaft 32, which is adapted to rotate normally in a clockwisedirection, Figs. 2 and 3, for the actuation of the hood structure in themanner above described. Said shaft 32 carries at each end a crank 33,and each of these cranks 33 has pivotally attached thereto a connectingrod 34,y the other endsr of which are pivotally connected to the longarms of the adjacent bell cranks 14, at the points of connection of saidlong arms with the lugs 20 of structure 15. In this way it will be seenthat a half revolution of the shaft 32 is adapted to effect one completeoperation of the hood structure, in the act of reversing; as the cranks33 move through the lower half of their travel, the hood structure iscarried over to the left, from the position shown in Figs. 1, 2 and 3,while when the cranks 33 move through the upper half of their travel,the mechanism is moved from its extreme left hand position back to theposition illustrated in igs. 1, 2 and 3.

As in my aforesaid Letters Patent, each gas flue terminal 9, 9 isequipped with a swinging closure 35, and in the present instance saidclosure 35 is fast on a hollow trunnion shaft 36, the latter takingbearing in alined slots 37 of a pair of brackets 38 that are formed onthe bottom of water seal casting 10, adjacent the flue terminal 9.

.The shaft 36 is fed with water from a supply connection 39, and theother end of said' sha-ft is connected by a coupling 40 with a waterpassage 41 that follows the rim of the closure 35, and discharges at 42into the water seal casting 10. It will be seen that owing to the mannerin which the hoods 18 are erected on the structure 15, the closure 35 ismade easily and quickly available, for purposes of adjustment or repair,since it is possible to withdraw the hoods 18 without disturbing thebase structure on which they are mounted. Furthermore, the covers 35 arereadily replaceable, owing to the disposal of the shaft 36 in the openbearing slots 37.

Each cover 35 is formed with a projecting lug 43, for cooperation with ashoe 44 secured to the adjacent end portion of water seal flange 17. Inthe position of the parts illustrated in Figs. 1, 2 and 3, said shoe 44,bearing on the lug 43, holds the closure' 35 in raised position, andthus provides for the flow of gas from the flue terminalV 9 to the flueterminal 5, which latter is connected to the gas regenerator passage 2of the furnace, Figs. 5 and 6. The movement of' the hoods 18 to theirother or left hand positions as above described, for the purpose ofreversing the furnace, allows the closure 35 to descend by gravity, soas'toco'ver and effectually seal the terminal 9. The arrangement ofparts is such that the closure 35 moves its full distance downwardly andseals the terminal 9 before the flange-17 is entirely lifted out of thewater in casting 10. In this way the escape of any gas past the fineterminal 9 during the operation of reversing is effectually prevented,since the closure 35 descends fully, and makes a water seal around saidiue terminal before the water seal made by the flange 17 is broken.

lVith the reversing mechanism in the position illustrated in Figs. 1, 2and 3, theY structure 15 is so disposedl as to maintain a damper orcover 45 in operative relation to the air regenerator fine terminal 6.This damper 45 is pivoted at 46 to a pair of lugs 47 that project fromthe end of structure 15, and the position of said damper may becontrolled, manually or otherwise, by a chain or connection 48, so as toregulate the quantity of air which enters the furnace through the flue6. It will be seen from Figs. 5 and 6 that when one of the reversinginstrumentalities 4 is in the position illustrated in Figs. 1, 2 and 3,the other reversing instrumentality 4 is necessarily in the otherposition,

Cil

or reversed from the illustrated position. In this reversed position,the hood 18 will have been moved away from 'the flue terminal 9, and thelatter will be covered and sealed by the closure 35; the flue terminal 5will be connected by said hood 18 to the adjacent stack flue terminal 7;while the air regenerator flue terminal 6 will be connected by the otherhood 1S to its adjacent stack flue terminal T. r)lie damper 45, underthese conditions, will be carried into an inoperative position, beyondthe terminals of all the flues.

It will be understood that the reversing instrumentalities d, d areidentical in all respects; by the present arrangement, suoliinstrumentalities, when provided in duplicate, are sufficient to tallecare of the entire reversing function of a furnace. Each instrumentalityfunctions with respect to both air and gas, in other words, thenecessity for separate and independent air and gas valves is eliminated.Moreover, it will readily be seen that the mechanism herein specifiedlends itself either to the arrangement shown in Fig. 5, where the gassupply is brought in at the ends, or to the arrangement shown in Fig. 5,where the supply is brought in at the center. Under either of the aboveconditions, and also when the reversing instrumentalities are placed atthe ends rather than at the side of the furnace, it will be clear thatthere is no hindrance against placing said instrumentalities in loseproximity to the air and gas regenerator passages of the furnace, whichresults in greatly reducing the lengths of the underground dueconstruction in devices of this class, with a consequent reduction inthe wastage of gas when the furnace is reversed.

For the control of motor 26, the shaft 32 has secured thereto, within acasing 49, a wheel 50, the rim of which rotates in contact with a pairof brushes 51 that are carried on an arm 52 which is loosely journalledon shaft The brushes 51 are in an electrical circuit which includes anautomatically operated switch for causing the stoppage of the motor 26;this circuit is completed by the metallic rim of wheel when said brushesare in contact therewith. Said metallic rim has two fiber or non-conducting inserts 53, located 180O apart; when either of these lieopposite and in contact with the brushes 5l, the electrical circuit isbroken, and as a result the motor switch is opened so as to discontinuethe operation of motor 26 after each half revolution of shaft 32, which,as above stated, is the amount of movement required for the reversal, ineither direction, of the mechanism shown in Figs. i. 2 and 3. Undernormal conditions therefore, with a predetermined setting 0f the armthat carries the brushes 5l, the starting of motor 2d to bring about thereversal of the apparatus, is followed by the automatic stoppage of saidmotor after the shaft 32 has made a half revolution, thus moving thehood structure either to the right or to the left, as the case may be.

Under certain conditions however, it may be desirable in the act ofconnecting the flue terminals 5 and 9, to swing the closure 35 only partway open, instead of all the way open, and thus to obtain a partialthrot tling of the gas supply to the furnace. This may obviously beaccomplished by manipulation of the arm 52 carrying brushes 51 so thatthe stoppage of motor 26 takes place earlier than normally, that is,before the shoe it-l moves the limit of its distance downwardly in thewater seal casting l0. It is to be understood, of course, that thisvariation in the opening of cover in no wise affects the other functionsof the mechanism, since such variation only occurs after the water sealhas been completely established by flange 17. In this way it will beseen that the apparatus affords a means for interrupting the descent ofthe hood structure before the limit of such descent is reached, wherebyto vary the volume of gas admitted to the furnace.

Provision is also made for controlling the position of cover 35 afterthe latter has been opened to its full extent in the normal or usualoperation of the apparatus. This involves the running of motor 26 in thereverse direction so as to raise the hood structure a sufficient amountto allow the gravity closing of cover 35 to the point desired. To thisend, the wheel 50 is provided with a fiber ring 54 having a segmentalinsert of conducting material which is adapted to be brought intocontact with a pair of stationary brushes 56. The parts are so arrangedthat during the contact of both of these brushes with the metal insert55, the motor 26 is subject to reversal of its direction by suitableagencies for this purpose, not shown, which may be conveniently locatedon the furnace floor, for manipulation by the operator. That is to say,the brushes 56 form part of an electrical circuit through which thisreversal in the direction of the motor is accomplished, said electricalcircuit being completed when both brushes are in contact with thesegment 55. The range through which the motor is reversible isequivalent, approximately, to the range of movement of closure 35; inother words, the segment is of such a length, and is so disposed withrespect to the brushes 56, that the motor reversing circuit is completedonly in that part of the rotation of shaft 32 that procures themovement. of said closure. 1t will readily be seen therefore, that afterthe closure 35 has been swung upwardly to the limit of its movement bythe complete descent of the hood structure, as shown in Fig. 3, it ispossible for the operator on the furnace floor to start the motor 26 inthe reverse direction, so as to cause a slight elevation of the hoodstructure and a consequent lowering of the closure 35. This actionhowever, is limited by the duration of contact of both brushes 56 withthe segment 55, and it cannot be continued past the point where theclosure 35 cuts olf the flow of gas from the flue terminal 9.

I claim: n

1. The combination with a regenerative furnace, of reversing apparatustherefor constituted by two movable devices, each device, in oneposition, controlling the flow to said furnace of both air and gas andin the other position, controlling the flow from said furnace ofproducts of combustion.

2. The combination with the air and gas passages of a regenerativefurnace, of reverslng apparatus for said furnace constituted by twomovable devices, each device providing for the inflow ofy gas and airand for the outflow of combustion products.

3. The combination with a regenerative furnace havinv a set of air andgas passages at each end, of reversing apparatus for said furnaceconstituted by two movable devices, one at each end of the furnace, forcontrolling respectively the corresponding set of assages, for theinflow of gas and air and the exit of combustion products.

4. A reversing mechanism for a regenerative furnace constituted by twomovable reversing devices, each adapted for connection with both the airand the gas fines at each end of said furnace to control the inflow ofgas and air and the exit of combustion products therethrough.

5. In apparatus of the class described, the combination with a set 0ffurnace flues, of a frame member movable selectively into differentpositions with respect to the terminals of said flues an-d having aflange adapted to water seal different pairs of said terminals, and ahood detachably supported by said frame member, `and adapted toestablish communication between the terminals that are water sealed bysaid flange.

6. In apparatus of the class described, the combination with a set offurnace fines, of a member movable selectively into different positionsto water seal the terminals of different pairs of said fines, a coverfor the terminal of o-ne of said flues adapted to be opened and closedby the movement of said member, and a hood detachably supported by saidmember for establishing communication between said pairs of water sealedterniinals.

7. The combination, with each set of air and gas and stack flueterminals of a regenerative furnace, of a movable reversing devicetherefor, a cover for one of said terminals adapted to be opened andclosed by the movement of said reversing device, and

means carried by said reversing device for controlling theflow of airinto another of said terminals.

8. The combination with each set of air and gas and stack flue terminalsof a regenerative furnace, of a movable reversing device therefor,adapted to establish communication, selectively, between different pairsof said flue te-rminals, a self-closing cover for one of said terminalsadapted to be opened by the movement 'of said device into operativerelation to said terminal, and means carried by said device forcontrolling the flow of lair into another of said terminals.

9, The combination with a regenerative furnace, of a reversing devicetherefor having a parallel motion, and expansive means, made availableby one portion of said motion, for providing a force adapted to assistin procuring another portion of said motion.

l0. The combination with a. regenerative furnace, of a reversing devicetherefor rhaving a parallel mot-ion, and expansive means, made availableby the gravity component of said motion, for providing a force to assistin procuring the reverse portion of said motion.

ll. In a mechanical movement, a member constrained for parallel motionwith respect to a pair of liXed centers, arms extending from saidcenters in opposite directions, and an expansible connection betweensaid arms.

12. The combination with a regenerative furnace, of a movable reversingdevice therefor.l bell crank levers at each end of the latter, havingcorresponding parallel arms connected to said reversing device, wherebyto constrain a parallel motion of the same, the other arms of said. bellcranks extending in opposite directions, and an expansible connectionbetween the ends of said other arms.

13. The combination with a regenerative y furnace, of air, gas and stackflues leading from each end thereof, and terminating adjacent oneanother, and a single reversing device operatively related to each setof air, gas and stack flue terminals let. The combination with aregenerative furnace having a set of air andv gas fines at each end, oftwo duplicate reversing devices, each associated with the terminals ofone of said sets of ilues, said two devices constituting the entirereversing means for said furnace, and means for operating said twodevices to effect the reversal of said furnace.

I5. The combination with a regenerative furnace, of a set of air and gasues for each end thereof, a pair of stack flue terminals interposedbetween the terminals of each pair of air and gas fines, a gas supplypassage having a terminal adjacent the terminal of each gas flue, andmovable means associated with each set of flue terminals for controllingthe direction of the products of combustion through said furnace.

16. The combination with the two sets oi air and gas passages of aregenerative furnace, of a pair of stack fine terminals interposedbetween the terminals of each set of air and gas passages, a gas supplypassage havinoF a terminal adjacent each gas passage terminal, andreversing means associated with each set of terminals.

17. The combination with the two sets of air and gas passages of aregenerative furnace, of a single stack passage associated with each ofsaid sets, and having a. pair of terminals interposed between theterminals of said air and gas passages, a gas supply,7 passa-ge having aterminal adjacent each gas passage terminal` and a movable reversingunit operative With respect to each of said sets of terminals.

18. The combination with a regenerative furnace, of a movable reversingdevice therefor adapted in one position to connect said furnace with asupplg7 of gas, actuating means for said device, and means forcontrolling said actuating means to varv the suppl)7 of gas admittedthrough said device to the furnace.

19. In apparatus of the character described, the. combination with a setof furnace tiues, of a cover for the end of one of said fines, a movablereversing device operative with respect to said tlues, and adapted byits movement to open said cover, means for actuating said reversingdevice, and means for controlling said actuatingr means to var;7 thedegree of opening of said cover.

20. In apparatus of the character described, the combination with a setof fin*- nace fines, of a cover for the end of one of said iues, amovable reversing device operative with respect to said tiues. andadapted by its movement in one direction to open said cover, anactuating means for said reversing device normally operative in onedirectiorn and means for reversing said actuating means within a`predetermined portion of the movement. of said reversing device,wherebyv to vary the degree of opening of said cover.

2l. In apparatus of the character described, the combination with a setof furnace iues, of a cover for the end of one of said fines, a movablereversing device operative with respect to said flues, and adapted byits movement in one direction to open said cover, an actuating means forsaid reversing device, normally operative to discontinue the movementthereof after a predetermined travel, means for controlling saidactuating means, to obtain a predetermined opening of said cover, andmeans for reversing said actuating means to var v the position of saidcover.

Q2. In apparatus of the class described, the combination with aregenerative furnace, of a single movable reversing device thereforadapted to control the inflow of both gas and air and the outflow ofcombustion products at one end of said furnace, and means associatedwith said device for segregating at all times the air and gas flowingtherethrough.

23. In apparatus of the class described, the combination with a set ofair, gas and stack iiues of a regenerative furnace, of a single movablereversing device controlling the inflow of gas and air and the outflowof combustion products, and cooperating with said fines to reverse thetravel of the products of combustion through said furnace, and meanscarried by said device for isolating, in all positions of said device,said air and gas fiues from each other.

Dated this fourteenth dav of December.

GEORGE H. ISLEY. iVitnesses NrLLIE I'THALEN, Gro. H. KENNEDY, Jr.

